iron

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Study how iron ore is mined with explosives and crushed and concentrated with remote-controlled machines

Explore an interactive periodic table of the elements

Figure 19: Summary of shock-wave data on the densities of oxides and iron compounds at high pressures and high temperatures. The seismologically derived pressure-density curves for the lower mantle and outer core are included for comparison.

global distribution of iron on the Moon's surface

Figure 9: Structures of some native elements. (A) Close-packed model of simple cubic packing of equal spheres, as shown by iron. Each sphere is surrounded by eight closest neighbours. (B) Close-packed model of the structure of arsenic and antimony. Flat areas represent overlap between adjoining atoms. (C) Partial representation of the structure of diamond. (D) The structure of graphite with sheets perpendicular to the c axis.

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Science & Tech

iron

chemical element

Also known as: Fe, ferrum

Written and fact-checked by The Editors of Encyclopaedia Britannica

Last Updated: Mar 5, 2024 • Article History

iron

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Category: Science & Tech

Key People:: William Kelly; Georgina Hope Rinehart; Jamsetji Tata; Langley George Hancock; Abraham Darby

Related Topics:: ferroalloy; alpha iron; delta iron; beta iron; gamma iron

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iron (Fe), chemical element, metal of Group 8 (VIIIb) of the periodic table, the most-used and cheapest metal. atomic number 26 atomic weight 55.847 melting point 1,538 °C (2,800 °F) boiling point 3,000 °C (5,432 °F) specific gravity 7.86 (20 °C) oxidation states +2, +3, +4, +6 electron configuration [Ar]3d⁶4s² Iron makes up 5 percent of Earth’s crust and is second in abundance to aluminum among the metals and fourth in abundance behind oxygen, silicon, and aluminum among the elements. Iron, which is the chief constituent of Earth’s core, is the most abundant element in Earth as a whole (about ...(100 of 1702 words)

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